Professor of Medicine, consultant physician and pulmonologist at the Obafemi Awolowo University Teaching Hospital, Ile-Ife, Osun State, Olufemi Adewole, tells LARA ADEJORO how early detection and treatment can curb tuberculosis
What is tuberculosis?
Tuberculosis is a chronic infectious disease caused by an organism called Mycobacterium TB. It affects mostly the lungs in more than 80-85 per cent of people and it can also affect other pulmonary organs like the brain, kidney, abdomen, uterus, bone, and others. It is the number one infectious disease killer worldwide and the 10th cause of death globally. TB is still one of the highest contributors to death among COVID-19 patients. It is an endemic disease that is highly prevalent in most low and middle-income countries like Nigeria and other parts of Africa.
Other various species like Mycobacterium TB and Mycobacterium Africanum can cause TB. They (Mycobacterium TB and Mycobacterium Africanum) are common species that cause TB in individuals. You have the non-TB mycobacterium; these tend to cause disease often in immune-deficient individuals. The non-TB mycobacterium tends to affect other parts of the body more often than the lungs.
Who is mostly affected by the disease?
TB affects anybody. It can affect the young and the old, especially in this part of the world where the disease is endemic, anybody can be affected. There are two forms of TB – Primary TB and Secondary TB. Primary TB usually affects an individual who has never had the disease before. So, the very first time you have exposure to the disease – either because you have direct contact with somebody who has the disease, or you were in the IDP camp, prison, or a health worker who had contact with individuals who had primary TB; they usually have symptoms that are not specific, like malaria-like symptoms which are easily transmissive, and many people may not know it. Most people overcome this but the organism lies dormant and can be active again.
When you have a second exposure to the organism, you will develop a secondary TB, or when the dormant organism gets reactivated in your body, you will have the secondary TB. Most of the people we see have a secondary TB because they were at one time or the other exposed to the disease and had developed some immunity against it. For anybody who has secondary TB, it means that the bacterium has been activated or the immunity becomes suppressed. So, individuals who have suppression of immunity either have HIV, diabetes or consume a lot of alcohol or smoke, or use certain drugs, and that can lead to the reactivation, and cause secondary TB.
Individuals who are vitamin D deficient are also at risk of having the disease. People who have cancer or kidney disease are at risk. Now, we have more people having organ transplants, kidney transplants, and they are also at risk of developing TB if not adequately evaluated and checked. When you get exposed to another TB case, you can have secondary TB also.
What is the prevalence rate of people who are affected in the country?
Nigeria ranks the sixth country with the disease in the world, which is about five per cent, and Nigeria has the highest TB burden in Africa. The prevalence rate for Nigeria has been done some three years ago, and it is more than three times what has previously been taken as the prevalence. Nigeria has over 400,000 TB cases annually but less than 30 per cent are detected. Nigeria has one of the highest low-case detection rates, though this is getting better now. That means we have a large number of people living in the community who are not detected.
How does it spread?
The disease is transmitted majorly through aerosols. When you have individuals who have pulmonary TB and when they cough, yawn, sing, laugh, or even talk, they can release the droplet nuclear into the atmosphere and remain suspended for a variable period; an individual can inhale it, and it can spread from there and move up to the respiratory tract, that seems to be the commonest way of inhaling droplets. Any individual that lives in a crowded environment and because there is no cross ventilation to disperse this disease, any other person in that room can easily inhale it. Sometimes, it could be transmitted in a laboratory.
How can someone know that he has the disease?
The majority of us in Nigeria already have a primary TB which we have probably overcome. So, anybody that is coming down with TB now is mostly secondary TB. The symptoms are common in the lungs, and you have things like cough, weight loss, excessive night sweats, coughing out of blood, and low-grade fever, especially in the evening time. Sometimes, when the disease has progressed, and it is going on for a long time, the person can become tired easily. The cough is productive of the sputum, and it may be coloured, it can initially be whitish, and it can have blood stain. This cough does not need to be a long-standing cough before it is TB. If someone is coughing for two weeks, it could be TB, and we usually tell people not to wait for their cough to be chronic before finding out what it is. For any cough of two weeks, you should suspect TB, and be screened for that.
Coughing out blood is one of them, and sometimes that is what makes patients come to the hospital because they are afraid of it. There are other things you need to evaluate, but in our environment, anybody that is coughing out blood must suspect TB. When you have neck swelling that is painless and progressive; sometimes, the swelling discharges pus on and off. If TB affects other parts of the body, you may have that symptom related to that organ, as well. It may affect the abdomen, the bones, the lumber bone, or the heart, kidney and brain, and the symptoms may be different. It can also affect the reproductive tract in both males and females. TB is one of the factors responsible for infertility because it can affect the tract and make it difficult for them to have a conception. It can also affect the male, and it can reduce spermatozoa production which can affect fertility. TB can affect any part of your body from the crown of your head to the sole of your feet.
Can a pregnant woman transmit TB to an unborn child?
A pregnant woman can transmit to her unborn child and give birth to what we call a congenital TB, which can affect virtually all the systems in the unborn child, but we don’t want that to happen. So, pregnant women who have TB should be treated. Treatment is safe for pregnant women. When you are being treated as a pregnant woman, your unborn baby is also protected. The saying that taking anti-TB drugs during pregnancy will affect the baby is a myth. If you’re pregnant, your baby is safe if you are on TB drugs. Sometimes, if it doesn’t affect the baby directly, it can cause stillbirth, pregnancy loss, or intrauterine growth retardation.
Experts say that the disease is curable when detected early. Does it mean that it can’t be cured when detected late?
The implication of late detection can lead to complications like spreading beyond the lungs, individuals may become anaemic, and that may lead to requiring a blood transfusion. The disease may become extensive in the lungs, and the patient will become tired, and restless. The complications make it more expensive to manage because you have to be admitted to be managed and treated. In the community, late detection enhances spread because when you have it and it is detected on time, then you break the circle of transmission, but when you have it and it is not detected on time, then you’re spreading the disease the more.
It can be cured at any point, even when detected late. The organism that is causing TB is eliminated from the body using medications. Whether late or early, TB is curable, but we don’t want individuals to come late because it can lead to complications. TB is not a death sentence, so it is curable if you take the medications as prescribed.
Can people contract the disease through kissing or sharing kitchen utensils?
It is possible in kissing because you can have the aerosol in the secretion in kissing but usually, it is not commonly transmitted through sharing kitchen utensils. So, as not to stigmatise our patients, we don’t discourage using kitchen utensils, but that doesn’t mean there will not be some form of universal caution that should be taken. When someone has TB and starts taking the medication, within the first three weeks, the burden of the organism is drastically reduced, and the risk of transmitting it is reduced.
How can it be treated?
Treatment is by using anti-TB medications of different forms. Treatment is usually for a long period but not for life. If you have TB that is not drug-resistant, treatment may be for six months or four months. The four-month treatment regimen is recently adopted and rolled out by the World Health Organisation. However, if you have drug-resistant TB, treatment may be as long as six months or nine months, but the good thing is that unlike before, treatment can go on for 18 months or more. Again, you don’t have to be admitted to the hospital to be treated, and you don’t need to take injections.
The good thing about anti-TB medications is that treatment is free, available in most TB treatment centres, most local government areas in Nigeria, and most tertiary hospitals, and testing is free.
Can you throw more light on drug-resistant TB?
It’s a form of TB in which the organism is not responsive to the usual medication. There are two forms of resistance – the primary resistance to which the organism has some mutations that make it resistant to anti-TB drugs, which are common, and the second resistance is individuals who are not compliant with the medications or individuals who have comorbidities like HIV and are at risk of having the secondary resistance. The most feared one is multi-drug TB, which means you are resistant to Rifampicin and Isoniazid. When you have resistance to these two drugs, you are said to have multi-drug resistance TB.
How can it be prevented?
Prevention is universal, and precaution is important. When you have TB, you have to cough into your elbow, cough in the tissue, and dispose of it. Don’t cough and be spitting around. Also, BCG immunization has been helpful. Immunization is not absolute, but it prevents individuals from the severe form of TB, and the protection can last for 17 years in an individual. It is essential to vaccinate the newborn baby among other immunisation that the baby is taking. We encourage people to eat a balanced diet, exercise, do not take alcohol. If you have diabetes, ensure that it is well controlled.
Another prevention method is detecting people with latent TB; they have the disease in the body but it is not manifesting symptoms. A large number of Nigerians are latently infected because of our situation, but the number of individuals whose risk reactivation is very high, like under-five children, healthcare workers, a patient living with HIV, or diabetes, and people who have other lung diseases. Such individuals must be tested for latent TB. Also, individuals who are preparing for transplant or individuals who are preparing for immunosuppressive drugs for a fairly long time should be tested for latent TB as part of prevention. Treating latent TB will prevent them from having active or secondary TB.
Treatment for latent TB is quite different from that of active TB. So, you must be distinctively tested and detected. If you don’t take care of people with latent TB, then you keep having more patients with active TB. Nutrition and awareness are very important. When you have symptoms of TB, it doesn’t cost you anything to go for testing. So, part of prevention is early testing.
What is hindering Nigeria’s efforts in eradicating this disease?
It’s a big issue. It cuts around everything – awareness, stigma, cultural beliefs. The myths around the disease and using traditional medicine hinder people from coming for treatment. We need to have a patient centre diagnostic pathway, which should be less cumbersome for patients. We should also look at attempts at other diagnostic methods other than sputum; urine could be used, and we also have the sweat test. We need to do active case finding. The only people that we see are those who come to the hospital, but we don’t go out to look for people who may have it and are not coming to the hospital. We have done this in the time past in the community where we did active case finding. The result was mind-boggling. We need to go to communities, give them health education awareness, screen them, and with that, we can detect those who may have it. Funding may also be a problem. We need more money to fund various programme aimed at detecting and tackling diseases. We need internal funding apart from the ones coming from donor funding.
What is the significance of World TB Day marked every March 24?
It’s a day set aside for creating awareness, advocacy, driving political will, and getting support for the eradication of TB. This year’s theme is ‘Yes! We can end TB.’ With this, we can get more people involved in the fight against TB and encourage people who have it to come out for free treatment. It is also a way of encouraging the adoption of research that can help eradicate the disease. The day is also an opportunity to make a clarion call to the national and the international government to adopt the innovative approach to treatment and diagnosis. The idea of ‘The End TB Strategy’ is to reduce the disease by 80 per cent, reduce death from TB by 90 per cent, and eliminate catastrophic costs for TB-affected households by 2030.
